By "looker," I don't mean the old-fashioned word for "babe." I'm referring to people who are curious about online dating, maybe even enough to post a profile and contact people, but have no real intention of actually meeting in person. More often than not, these are people who have, to use another old-fashioned word, too much "baggage."
One giveaway that you're corresponding with a looker might be that they delay meeting you in person. Or take too long to respond. It can be difficult to weed these folks out from the normal and well-adjusted. I jest, but truthfully we have all been That Guy (or Girl) at some point. They're not bad people; they're just not finished working through something, aren't ready to date and might hurt you because they don't really know what they want. In other words, they're a waste of your time.